Impact absorbing article of footwear



May 10, 1949. c. T. LEE 2,469,969

IMPACT ABSORBING ARTICLE OF FOOTWEAR Filed June 9. 1947 INVENToR, 7e/m 7.' e s BY MSM Airy.

@atented May l@ i949 unirse STATES rnrreisi'r orricr.

IMPACT ABSORBING ARTICLE F FOOTWEAR Clement T. Lee, Cleveland, Ohio Application June 9, 1947, Serial No. 753,459

8 Claims. (Cl. SI5- 7.8)

This invention relates to impact absorbing shoes, and especially to a removable overshoe particularly adapted to withstand relatively heavy impacts, such as received by a para'chutist in striking the earth.

Heretofore there have been various types of rubber soles and cushioning members provided for shoes, such as would be worn by a parachutist or by a person working in the vicinity of vibrating machinery or by people who are especially sensitive to foot shocks when working on a steel or concrete floor for long periods of time. However, such special cushioning members provided for shoes have not been sturdy enough nor load absorptive enough to give desirabl-e action when subjected to extremely heavy impacts, such as those occasioned when a parachutist strikes the earth.

The general object of this invention is to provide a new and improved article of footwear especially adapted for receiving and cushioning heavy impacts.

A further object of the invention is to provide an eiective, removable cushion overshoe for a parachutist. v

, Another object of the invention is to provide an inexpensive, easily manufactured overshoe that has a removable impact absorbing member.

Another object of the invention is to provide an impact absorbing member having adjustable load supporting and shock absorbing characteristics.

The foregoing and other objects and advantages of the invention will be made apparent as this specication proceeds.

Reference now is made to the accompanying drawing wherein:

Fig. 1 is a perspective view 4or' a parachutist boot having an overshoe embodying the principles of the invention engaged therewith; and

Fig. 2 is an enlarged vertical section through the overshoe of Fig. 1 with the boot indicated in broken lines as occupying the overshoe.

With particular reference to the details shown in the drawing, the invention is illustrated as incorporated in an overshoe. generally indicated at IIJ. It is adapted to be applied in the usual .manner to a shoe or boot, such as the parachutist boot il shown. The overshoe I 0 is made from any conventional material and it usually comprises either natural or synthetic rubber which is formed into the shape of a foot portion of a shoe to form an enclosing member I2. In some instances, this enclosing member may be reinforced with fabric. but in all events, it is desired that said enclosing member I2 be somewhat 2 elastic and normally slightly smaller than the `foot portion of the shoe or boot with which it is to be engaged. Thus, the' enclosing member of the overshoe I0 will be expanded slightly when engaged with the shoe of the person wearing the same and thenatural properties of the enclosing member will retain it in tight engagement with the shoe of its wearer. The enclosing member I2 is shown as provided with a continuous downwardly directed rib portion or shoulder i3 on its inner surface and such shoulder I3 is adapted to engage with a load distributing member such as a plate I4 which is of solid construction so that a person wearing the overshoe i0 will be supported on the plate I4.

As a salient feature of the invention, a combined rubber pad and air cushioning device is provided below the plate I4 for receipt and absorption of load and shock applied to the overshoe I0 by its wearer, such as when the person wearing the overshoe would strike the earth after a `parachute jump.` The novel load supporting element of the invention comprises a rubber pad I5 which is positioned in the lower portion of the enclosing member I2 and may be sealed within an inflatable envelope I6 but does not completely fill the same. The envelope IS may be made of rubber or rubberized fabric or other desired material and it is shown as removably positioned in the overshoe. A conventional inflation device, such as a valve II, is incorporated in the envelope I6 so that the air pressure set up therein can be varied whereby the load supporting and shock absorbing characteristics of the combination of the rubber pad I5 and the envelope I6 can be adjusted to a desired value for the individual wearer of ythe overshoe II). The rubber pad I5 is shown as of a closed cell construction wherein the individual cells I8 have gas pressure set up therein but this pressure does not vary appreciably with variations in the air pressure within the envelope I6. This closed cell rubber of which the pad I5 is made can be formed by any of a number of conventional methods but if it is desired to vary the pressure within the rubber pad I5, as well as the pressure in the envelope IE, then one should use another type of cellular rubber wherein the cells are intercommunicating with some of them opening exteriorly of the pad whereby the same pressure would be set up within the rubber pad as would exist within the envelope i6.

Fig. 2 als-o shows that a relatively .thick sole I9 is provided on the enclosing member I2 and this sole, like the remainder of the enclosing member, may be formed of any conventional conananas the overshoe i9. By means of a suitably shaped Y instrument, capable of convenient insertion between the side wall of the overshoe and the adjacent part of the boot or shoe of the wearer, the valve may be opened by depressing its stem to relieve the air pressure. This is desirable after a parachutist lands, before proceeding on foot.

While it has been stated that the shoulder I 3 is continuous, it will be realized that this shoulder may be provided in the shape of spaced lugs formed, usually, integral with the enclosing member and possibly such spaced lugs could only be formed at, for example, four circumferentially spaced portions within the enclosing member. This would facilitate engagement of the plate I4 with the shoulders but would not change the load transmitting relationship of the construction shown.

While one complete embodiment of the invention has been illustrated and described herein in detail, it will be realized that modifications of this construction may be made without departing from the scope of the invention as deiined in the appended claims.

Having thus described my invention, what I claim is:

1. An overshoe of the class described comprising an enclosing member made of an elastic material and adapted to be removably engaged with the foot portion of a shoe, said enclosing member being of such normal size as to be expanded when engaged with a shoe to compress against it tightly, said enclosing member having a downwardly directed Ishoulder formed on its interior spaced from the lower portion thereof, a plate member positioned in said enclosing member and engaged with said shoulder to be retained against upward movement thereby, a rubber pad positioned within said enclosing member below said plate member but not iilling such space completely, an innatable member positioned around said rubber pad, and means for inilating said inilatable member so that the pressure therein can be controlled to vary the load `supporting and shock absorbing characteristics of the overshoe.

2. An overshoe of the class described comprising an enclosing member made of an elastic inaterial and adapted to be removably engaged with the foot portion of a shoe, said enclosing member being of such normal size as to be expanded when engaged with a shoe, said enclosing member having a downwardly directed shoulder formed thereon spaced from the lower portion thereof, a plate member positioned within said enclosing member and engaged with said shoulder to be retained against upward movement thereby, a rubber pad positioned within said enclosing member below said platemember, an inflatable member positioned around said rubber pad, and a valve for said inilatable member so that the air pressure; therein can be controlled to vary the load supporting and shock absorbing characteristics of the overshoe.

3. An overshoe adapted to absorb impact load for the wearer, which overshoe comprises an elastic foot enclosing part adapted to retain itself in engagement with the foot of its wearer, an innatable member received in said overshoe, a rubber pad enclosed in said member to provide a combined air and cushion load receiving device, and means for distributing load over the surface of said inflatable member and said rubber pad.

4. An overshoe as in claim 3 wherein a valve is provided for said inflatable member and it extends therefrom up through said load distributing means into the shank portion of an article of footwear that occupies the foot enclosing part of the overshoe.

5. An article of footwear adapted to absorb impact load for the wearer, said article comprising a foot enclosing part and a hollow sole that opens substantially throughout its entire area into the bottom of said foot enclosing part, a load supporting and shock absorbing cushion means occupying the hollow sole and adapted to be inserted into the same through said foot enclosing part, and a detached relatively stiff load distributing element disposed over said cushion means and constituting the bottom of the foot enclosing Dart.

6. An article of footwear according to claim 5, wherein the article is formed with integral parts for retaining s'aid load distributing element against upward displacement.

7. An article of footwear according to claim 5, wherein said cushion means consists of an inflatable envelope and a resilient pad.

8. An article of footwear according to claim 7, wherein the resilient pad is permanently enclosed within said inflatable envelope.

CLEMENT T. LEE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name i Date 1,711,302 Belpedio Apr. 30, 1929 1,942,883 Schaller Jan, 9, 1934 FOREIGN PATENTS Number Country Date 317,846 France June 7, 1902 

